Panel wall construction

ABSTRACT

A PLURALITY OF PANELS OF SANDWICH CONSTRUCTION EACH HAVING SPACED WALL ELEMENTS, A CORE AND A PERIPHERAL FRAME BETWEEN THE WALL ELEMENTS. THE FRAME PROVIDES TONGUES AND COOPERATING GROOVES FOR RECEPITION OF THE TONGUES OF ADJACENT PANELS WHEN THE PANELS ARE DISPOSED IN END-TO-END ENGAGEMENT. ANCHORING SCREWS EXTEND THROUGH FRAME PORTIONS OF ADJACENT PANELS TO RELEASABLY LOCK THE PANELS IN WALL FORMING END-TO-END ENGAGEMENT.

E. W- GUSTAFSON PANEL WALL CONSTRUCTION Nav. 23, 1971 3 Sheets-Sheet l Filed April 13, 1970 INVENTOR. EVER-r W GUSTA Fsc/v yf/Z@ A TTOPNEYS NOV 23, 1971 E. w. Gus-Marsch; zhm

PANEL WALL CONSTRUCTION Filed April 13. 1970 E Sheets-Sheet 2 INVENTOR.

VERT W Gasp-A BY A T TOR/VE V5 New.D 23, N971 E. W. PANEL WALL CONSTRUCTION 5 Sheets-Sheet 1L Filed April 1s, 1970 a9 JN /M/ H0 :NVENTOIL A T Tow/VE Ys United States Paten 1;::1

3,621,624 PANEL WALL CONSTRUCTION Evert W. Gustafson, Box 1009, Fork Peck Highway, Glasgow, Mont. S9230 Filed Apr. 13, 1970, Ser. No. 27,844 Int. Cl. E04b 1/02, 7/02 U.S. Cl. 52--90 10 Claims ABSTRACT OF THE DISCLOSURE SUMMARY OF THE INVENTION An important object of this invention is the provision of wall structure of cooperating wall panels which may be prefabricated and easily shipped to a point of assembly and quickly and easily assembled.

Another object of this invention is the provision of Wall structure having panels and elements cooperating therewith to provide conduits for wiring, pipes, and public utility service elements generally.

Another object of this invention is the provision of a wall structure having connections between adjacent panels for holding the panels against relative transverse movement therebetween.

Yet another object of this invention is the provision of wall structure wherein means for locking adjacent wall forming panels together is largely invisible and inaccessible from the exterior of the wall structure.

To the above ends, a wall structure is provided comprising a plurality of panels in end-to-end engagement to dispose the panels in a row. lEach panel includes a pair of laterally-spaced generally rectangular wall elements, a core element of insulating material between the wall elements, and a peripheral frame between the wall elements adjacent the periphery thereof and encompassing the core element. The frame of one panel at one end of the row thereof has opposite end frame members defining longitudinally extending outwardly opening grooves. The frames of the others of the panels each have opposite end frame members, `one defining a longitudinal outwardly opening groove, the other providing an outwardly projecting longitudinally extending tongue for reception in the groove of the frame of an adjacent panel. The end frame members of each of the panels have transverse openings therethrough in alignment with given openings through the end frame members of adjacent panels for reception of anchoring screws that are threadedly received in nut elements secured to some of the end frame members. The anchoring screws connecting one panel to a second panel in a row thereof are disposed at different levels or points longitudinally of their end frame members and the anchoring screws connecting the second panel to a third one in the row thereof. Each panel is provided with enlarged passages through one end frame member and the core thereof to the anchoring screw receiving openings in the opposite end frame member for delivery of the anchoring screws to their respective openings from the opposite end of tbe panel. Closure elements are provided for exposed grooves at opposite ends of a row of panels to provide covered passageways for pipes, electrical wiring or any other utility service conduits or elements. Means is further provided for easy "ice connection of one row of panels to `one or more other rows angularly spaced therefrom to form floors, walls, and roofs of a building.

DESCRIPTION OF THE DRAWINGS FIG. l is a view in side elevation of a building structure utilizing the wall panels of this invention;

FIG. 2 is a view in top plan of the building of FIG. l;

FIG. 3 is a view in end elevation;

FIG. 4 is a view in plan of one of the wall elements of this invention, some parts being removed, some parts being broken away and some parts being shown in section;

FIG. 5 is an enlarged fragmentary section taken on the irregular line 5-5 of FIG. l;

FIG. 6 is an enlarged fragmentary section taken on the line 6-6 of FIG. l;

FIG. 7 is an enlarged fragmentary section taken on the irregular line 7-7 of FIG. 2;

FIG. 8 is a view in side elevation of another one of the wall panels of this invention, some parts being broken away and some parts being shown in section;

FIG. 9 is a View corresponding to a portion of FIG. 6, but showing a modified arrangement; and

FIG. l() is a fragmentary section taken on the line 10-10 of FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In FIGS. 1 8, a building structure is shown as comprising a pair of laterally-spaced vertical side walls each including a wall panel 1 and similar wall panels 2 and 2a, `vertically-spaced horizontal walls each comprising a horizontal wall panel 3 and similar wall panels 4 and 4a, and a pair of vertical end wall panels 5. As shown, the wall panels 1-5 are all of laminated or sandwich construction, diiering only in structural details. Each of the wall panels includes inner and outer wall elements, a core element sandwiched between. the wall elements, and a peripheral frame surrounding the core element and secured to the wall elements at the peripheral portions thereof.

More specically, the wall panels 1 each comprise rectangular inner and outer wall elements 6 and 7 respectively, a core element 8 of suitable insulating material sandwiched between the wall elements 6 and 7 and bonded thereto, and a peripheral frame 9 surrounding the core element 8 and bonded or otherwise rigidly secured to the adjacent inner surfaces of the wall elements 6 and 7 at the peripheral portions thereof. The wall elements 6 and 7 may be made from any suitable wall material, such as plywood, composition board or cementitious material, the peripheral frame 9 being extruded or otherwise formed from metal or synthetic plastic material.

The frame 9 comprises a pair of spaced vertical end frame members 10 and 11 at the opposite ends of the panel 1, and cross-sectionally U-shaped horizontal top and bottom frame members 12 and 13 respectively at the upper and lower edges of the panel 1. The end frame members 10 and 11 define laterally outwardly opening grooves 14 and 15 that extend longitudinally of their respective frame members 10 and 11, the top frame member 12 having a at intermediate portion 12 that is flush with the upper edge of the panel 1, the bottom frame member 13 defining a downwardly opening groove 16 that extends longitudinally between the end frame members 10 and 11. The end frame member 11 is provided with a plurality of longitudinally-spaced transverse openings 17 and has welded or otherwise rigidly secured thereto a plurality of nut elements 18 each in register or alignment with a different one of the openings 17. 'Ihe groove 14 of the end frame member 9 is normally covered by an elongated closure member 19 that extends the length of the end frame member v9l and is secured thereto by machine screws or the like 20, the closure plate 19 cooperating with the end frame member 9 to define an elongated passage 21 for .reception of wiring, pipes or any other public utility service elements, not shown.

The side wall panels 2 resemble the panel 1 in most respects, the same having inner and outer Wall elements 6 and 7 respectively, a core element 8, top and bottom frame members 12 and 13 and an end frame member 11. The panels 2 differ from the panels 1 in that the panels 2 are each provided with an end frame member :22 lnstead of an end frame member 10, the end frame members'22 each being formed to provide a longitudinally-extending laterally outwardly projecting tongue 23 that is nestmgly received in the groove 1'4 of an adjacent panel 1. The tongue 23 of the frame member 22 associated with the wall panel 2 is provided with transverse openings 24 aligned with the transverse openings 17 in the adjacent end frame member 11. Horizontal passages 25, aligned with each opening 24, extend through the opposite end frame member 11 of the panel 2 adjacent the panel 1, and through the core element 8 thereof, to permit insertion of anchoring screws 26 through the aligned openings 17 and 24 and screw threaded engagement with the adjacent nut elements 18, from the opposite end of the panel 2.

The panels 2a are substantially identical to the panels 2 differing therefrom only in the location of the passages 25. The passages 25 of the panels 2a are disposed at different levels from the passages 25 of the panels 2, and are each aligned with a different pair of aligned openings 17 and 24 in the end frame members 11 and 22 of the panels 2 and 2a respectively, these latter openings being aligned with other anchoring nuts 118 for reception of respective anchoring screws 26 inserted longitudinally through the passages 25 of the panels 2a. The groove 14 in the panel 2a, formed by the end frame member 11 thereof is covered by another closure plate 19 to provide a second passage 21. As shown in FIG. 5, this other closure plate 19 is secured to its respective end frame member 11 by screws 20. Although not specifically shown, the top frame members of the panels 2 and 2a are identical to the top frame members 12, the bottom frame members of the panels 2 and 2a also being identical to the bottom frame members 13. With reference to FIG. 8, it will be seen how the passages 25 in a given panel, in this instance a panel 2, are offset vertically or longitudinally of the frame member 11 from adjacent openings 17 in the same end frame member 11. With this arrangement, a side wall may be quickly and easily assembled by placing a panel 2 into tongue and groove engagement with a panel 1 and locking the panels together by inserting locking screws 26 through the passages 25 in the panel 2, through aligned openings 24 in the panel 2 and 17 in the frame member 11 of the panel 1, and screw threading the screws 26 into engagement with aligned ones of the nut elements 118 in the panel 1 by means of a socket wrench having an elongated shank. Thereafter, a panel 2a is placed into tongue yand groove engagement with the end frame member 11 of the panel 2 and assembled thereto in the same manner, the passages 25 in the panel 2a being aligned with the openings 17 in the end frame member 11 of the panel 2. Thus, it will be seen that, by alternating panels 2 and 2a, a wall of any desired length may be assembled.

The horizontal panels 3, 4 and 4a are quite similar t0 the normally vertically disposed panels 1, 2 and 2a, but are normally of somewhat heavier construction so as to act yas load-bearing floors and building roofs. In FIGS. 6 and 7, panels 3 are shown as being used for a door, supporting side wall panels 1, and as a roof or ceiling being supported by the side Wall panels 1 and end panels 5. Each panel 3 comprises an upper load-bearing wall element 27, a lower wall or ceiling element 28, a core 29 and a frame 30. The frame 30 includes opposite end frame members 3l. and 32, and identical opposite side frame members 33, the frame members 31-33 being substantially identical and defining outwardly opening longitudinal grooves 34. For adding load-bearing strength, a conventional I-beam 35 is disposed transversely of the end frame members 31 and 32, generally centrally between the side frame members 33, the beam 35 being welded or otherwise rigidly anchored at its opposite ends to the end frame members 31 and 32. To further stiffen or strengthen the panel 3, a plurality of stress rods or stress cables 36 extend through spaced transverse apertures 37 in the beam 35, each stress member 36 having nut-equipped tensioning screws 38 at its opposite ends extending through suitable openings in the side frame members 33 and adjustably secured thereto. With reference to FIG. 6, it will be seen that the openings 37 are disposed near the bottom of each beam 35, the tensioning screws 358 being disposed near the top wall element 27, so that tightening of the tensioning screws 38 places the members 36 unde1 tension to brace the beam 35 and maintain the panel 3 flat even under extreme loads.

The panels 4 and 4a are similar to the panels 3, the frames of the panels -4 and y4a having an end frame member 39 at one end of each thereof that is formed to provide a laterally outwardly projecting longitudinal tongue `40. The opposite end of each panel 4 and 4a, like the panel 3, is provided with an opposite end frame member 32 that defines a laterally outwardly opening longitudinal groove 34. With reference to FIGS. 1 3, 6 and 7, it will be seen that all of the grooves 34 not occupied by cooperating tongues 40, are covered by elongated closure plates 41 similar to the closure plates 19, and secured to the respective frame members by machine screws or the like 42. The closure plates 41 cooperate with their respective frame members 31-33 to define elongated passageways 43 for reception of pipes, wiring and the like.

The horizontally disposed panels 3, 4 and 4a are releasably locked together in the same manner as the vertical wall panels 1, 2 and 2a, the frame member 32 of the panel 3 having welded or otherwise secured thereto a plurality of nut elements 44 for reception of anchoring screws 45 that extend through aligned openings 46 and 47 in the frame member 32 of each panel 3 and tongue 40 lof an adjacent panel 4. Each panel 4 has a plurality of passages 48 therethrough extending from its respective frame member 32 to a different one of the openings 47 in the opposite tongue 40. Further, each frame member 32 of the panels 4 and 4a has secured thereto a plurality of nut elements `49 each in register with a different one of a plurality of openings 50 that are disposed in spaced relation longitudinally -of their respective frame members 32 to the passage 48 in the panel 4. The tongue 40 of each panel 4a is provided with openings S1 axially aligned with the openings 50 in the adjacent panel 4, for reception of other anchoring screws 45 that are inserted from the groove 34 in the frame member 32 at the opposite end of panel `4a through passages 52 in the frame members 32 andhcore elements 29, see particularly FIG. 7. As with the vertlcal panels 1, 2 and 2a, a door or roof structure of any desired length may be produced by adding alternating panels 4 and 4a.

As shown in FIG. 6, the bottom frame members 13 of the panels 1 and the adjacent edges of the wall elements 6 and 7 thereof are adapted to rest upon the top surface of an underlying horizontal panel 3. A pair of crosssec'tionally generally U-shaped frame members 53 are rigidly mounted on the top wall element of the underlymg horizontal wall panel 3 and secured thereto by bolts or the like 54. The U-shaped frame members 53 are upwardly opening, and are nestingly received in the grooves 16 of the bottom frame members 13 in opposing relation to the grooves 16. The U-shaped frame members 53 cooperate with their adjacent bottom frame members 13 to define passages 55 for wiring or the like, and the members 13 and 53 are rigidly but releasably secured together by machlne screws or the like 56. Although not specifically shown, it will be appreciated that the wall panels 2 and 2a are mounted on the underlying horizontal panels 4 and 4a by other U-shaped frame members 53, not shown, but in the same manner. With further reference to FIG. 6, it will be seen that an upper horizontal Wall panel 3 may be superimposed on the top edges of the panels 1 and rigidly secured thereto by bolts or the like 57 extending downwardly through suitable openings in the frame members 33 and screw threaded into the intermediate portions 12 of the top frame members 12. Other horizontal panels 4 and 4a, may be secured to the upper edges of panels 2 and 2a in the same manner.

The end wall panels 5 comprise inner and outer wall elements 58 and 59 respectively, core elements 60, and peripheral frames in 61 encompassing the core elements 60 and secured to the peripheral portions of the inner and outer wall elements 58 and 59. The inner and outer wall elements 5S and 59, and the core elements 60 are similar' to those of the wall panels 1, 2 and 2a. As shown in FIG. 5, the frame `61 includes side and bottom frame members 62, one of which is shown, these being substantially identical to the bottom frame members '13, and defining channels 63. Cross-sectionally U-shaped frame members 64, like the frame members 53 are nestingly received in the channels or grooves 63 of the frame members 61 in opposed relationship to the frame members 62, and rigidly secured to the end wall panels 5 by machine screws or the like 65. The U-shaped members 64 are rigidly secured to the adjacent side wall panels 1 and 2a by bolts 66, see particularly FIG. 5. As shown in FIG. 7, the frames 61 include top frame members 67 similar to the frame members 12 and having fiat-topped portions 68 which screw-threadedly receive anchoring bolts 69 which rigidly anchor the overlying ones of the horizontal panels 3 and 4a to tbe underlying end Wall panels 5.

It will be appreciated that, should it lbe desired to provide a building structure having a width greater than that of the horizontal wall elements 3, 4 and 4a and end wall panels 5, tongue and groove connections between a pair of such panels, similar to the connections between the wall panels 1 and 2 or 3 and 4 may be provided. Further, it will be appreciated that any of the panels 1, 2, 2a and 5 may, if desired, be provided with door and window openings, showing and description of these being omitted, in the interest of brevity.

MODIFIED FORM OF FIGS. 9 AND 10 The arrangement of FIGS. 9 and 10 illustrates how panels similar to the panels 3, 4 and 4a may be modified to provide a roof having upwardly converging portions such as a gable roof. As shown, the roof comprises upwardly converging pairs of panels 70 and 71, the panels of each pair thereof being connected together by tongue and groove connections 72, the pair off panels 70 being connected to the panels 71 by similar tongue and groove connections 73. It will `be noted that the panels 70` and 71 are quite similar in structure to the panels illustrated in FIGS. 1-8, having inner and outer wall elements 74 and 75 respectively and core elements 76, the tongue and groove joints 72 and 73 being portions of peripheral frames similar to the frames 9 and 611. A side wall panel 1, and end wall panels 5 are shown fragmentarily in FIG. 9, the roof panel elements 7() and 711 being supported on the end panels 5 by triangular wall elements 77. Similarly, the outer edge portions of the roof panels 70 and 71 are supported on the side panels, such as the panel 1, by triangular inserts 78, one of which is shown in FIG. 9. The panels 70 and 71 are rigidly secured t-o the underlying side wall panels by bolts 79, one of which is shown. For supporting the roof elements 70 and 71 intermediate the end walls of a building structure, and at the peak portion of the roof, I provide a vertically disposed supporting post 80 having a fiat upper plate-like end 81, an elongated horizontal plate 82 anchored to the upper end 81 by means of nut-equipped bolts 83, and a pair of laterally-spaced vertical triangular beams ,84 having laterally projecting lower lianges anchored to the plate 82 by the bolts 83 and other nut-equipped bolts `86. The beams 84 are further provided with laterally outwardly projecting flanges 87 that converge upwardly from opposite ends of the beams 84 and which engage and support the panels 70 and 71 adjacent the peak of the roof. The roof panels 70 and 71 are rigidly secured to the beams 84 by a plurality of bolts 88 extending through suitable apertures in the anges 87 and screw threaded into the overlying panels 70 and 71. The exposed ends and side edges of the panels 70 and 71 have outwardly opening grooves or channels 89, one of which is shown in FIG. 9, through which the screws 79 may be inserted and screw threaded into the upper edges of the panels 1, the channels 89 being covered by elongated closure plates 90, similar to the closure plates or members 19 and 41.

It will be noted that all of the joints or connections between adjacent panels and between panels and their respective closure plates may be sealed against leakage of dust or moisture by conventional and readily available caulking or sealing compounds, in the usual manner.

While I have shown and described a preferred embodiment and a modied arrangement of a wall structure, it will be understood that the same is capable of modification without departure from the spirit and scope of the invention, as defined in the claims.

What is claimed is:

1. Wall structure including a plurality of rectangular panels disposed in end-to-end engagement to provide a row of said panels; each of said panels including laterally spaced parallel wall elements, a core element secured between said wall elements, and a rectangular peripheral frame secured between said wall elements adjacent the periphery of said wall elements and encompassing said core element; each of said frames having a portion defining a groove extending longitudinally of one end of its respective panel and opening laterally outwardly of said one panel end; the frame of each panel but an end one in said row having a tongue extending longitudinally of the opposite end of its respective panel and projecting laterally outwardly of its respective panel for reception in the groove of an adjacent panel, the frame of said end one of the panels having a portion defining a groove in its opposite end similar to others of said grooves, the arrangement being such that grooves are disposed at the opposite ends of the row of panels; groove closure means co-extensive in length with said grooves and closing the outer open sides thereof at the ends of said row of panels to provide utility service carrying conduits; and means for anchoring said panels in said end-to-end engagement comprising a plurality of anchoring screws spaced apart longitudinally of said frame portions and extending through aligned openings in the tongues of said panels and adjacent groove orming portions of adjacent panels, and cooperating nut elements, the anchoring screws and their cooperating nut elements securing one panel to a second one of said panels at different longitudinally spaced points than the anchoring screws and cooperating nut elements securing said second panel to a third one of said panels.

2. The wall structure according to claim 1 in which each of said peripheral frames includes a pair of opposite end frame members and a pair of opposite side frame members, different ones of said end frame members dening said tongues and said grooves, each of said panels having passages through one end frame member and the core element to the opposite end frame member and in axial alignment with the screw receiving openings in said opposite end frame member, whereby said anchoring screws are introduced to their respective screw receiving openings, for engagement with cooperating ones of said nut elements, from an opposite end of each panel in the row thereof.

7 3. The wall structure according to claim 2 in which said side frame members comprise laterally outwardly opening channel members extending between the end frame members, said panels being adapted to be horizontally disposed to provide oor and roof structures selectively, characterized by closure mem-bers co-extensive in length with and secured to said side frame members and cooperating therewith to provide passages along opposite side edges of said floor and roof structures.

4. The wall structure according t-o claim 3 characterized by an intermediate frame member connecting the longitudinally central portions of said frame members in each of said panels, each of said intermediate frame members having a plurality of longitudinally spaced transverse openings therethrough, and a plurality of reinforcing crossties extending through said intermediate frame member openings and anchored at opposite ends to said side frame members.

5. The wall structure according to claim 2 in which one of said side frame members of each panel comprises a laterally outwardly opening channel member, the opposite side frame member having a llat outer surface, characterized by a cross-sectionally generally U-shaped frame member having flat side Wall portions and a generally at intermediate connecting portion nestingly received in each side frame channel member and in opposing relation thereto to deline therewith an elongated conduitlike passage, and means for releasably anchoring said U- shaped frame member in its respective channel member.

6. The wall structure according to claim 5 in which said flat intermediate portion of each generally U-shaped frame member is disposed yllush with the adjacent side edges of said inner and outer wall elements to provide therewith a flat outer side edge surface.

7. The wall structure according to claim 1 in which the wall elements of said panels are horizontally disposed to provide a oor structure; characterized by a second plurality of vertically disposed panels disposed in a row and extending upwardly from the floor structure adjacent one side edge of the liloor structure; said vertically disposed panels each including laterally spaced parallel wall elements, a core element secured between said wall elements, and a rectangular peripheral frame secured between the wall elements adjacent the periphery of the wall element and encompassing the core element; said frames of said second plurality of panels including vertical end frame members providing tongue and groove connections between adjacent ones of said vertically disposed panels, and horizontal top and bottom frame members; said bottom frame members defining downwardly opening grooves extending from end-to-end of its respective panel; and a plurality of upwardly opening channel members each nestingly disposed within a dilerent one of said downwardly opening grooves; and means releasably securing said upwardly opening channel members to said horizontally disposed panels and to said bottom frame members, said lbottom frame members and upwardly opening channel members cooperating to define a continuous passage from one end to the other of said wall structure.

8. The wall structure according to claim 7 in which the frame of a panel at one end of said row of vertically disposed panels comprises opposite end frame members both defining outwardly opening grooves, characterized by means for releasably securing said vertically disposed panels together in end-to-end engagement comprising a plurality of vertically spaced anchoring screws extending through aligned openings in the tongues of said vertically disposed panels and adjacent groove forming portions of adjacent vertically disposed panels; and cooperating nut elements; said last mentioned anchoring screws and their cooperating nut elements securing one vertically disposed panels to a second one of said vertically disposed panels at diiferent levels than the anchoring screws and cooperating nut elements securing the second vertically disposed panel to a third one of the vertically disposed panels; and an elongated closure plate secured to one end frame member of a vertical panel at one end of said row thereof.

9. The w'allstructure according to claim 7, characterized by a generally rectangular vertically disposed end wall panel comprising spaced apart inner and outer wall elements, a core element and a generally rectangular peripheral frame encompassing the core element between said last mentioned wall elements and secured thereto and to said wall elements; said last mentioned peripheral frame comprising horizontal top and bottom frame members and vertical end frame members; one of said end frame members defining an outwardly opening longitudinal groove; and means for releasably securing said end wall panel to one of said rvertical panels comprising an elongated panel member opposed to and nestingly received in the groove of said end frame member; screw means for securing said last mentioned channel member in said end frame member of the end' panel; and screw means extending from the end groove of one of said vertical wall panels and screw threadedly anchored to said last mentioned channel member.

10. The wall structure according to claim 1 in which said panels are disposed in a pair of rows of panels in edge-to-edge tongue and groove engagement, said rows being disposed in angularly spaced upwardly converging planes, characterized by connecting and supporting means for said rows and including a generally vertical supporting post, a rigid horizontal plate -xed on the upper end of said post, and a pair of laterally spaced vertically disposed beams on said plate; each of lsaid beams having a laterally outwardly projecting lower horizontal flange and a pair of laterally outwardly projecting upper flanges which converge upwardly from the opposite ends of the beam for engagement with upwardly converging pairs of said panels; and screw means for anchoring said beams to said horizontal plate and said upwardly converging panels.

References Cited UNITED STATES PATENTS 765,930 7/1904 `Mahony 52-580 1,747,313 2/1930 Miss 52-90 2,255,315 9/1941 Hamilton 52-264 X 2,825,098 3/1958 Hultquist 52-580 3,193,061 7/1965 Downes 52,-461 X 3,203,145 8/1965 Raynes 52-90 X 3,246,435 4/ 1966 Russell 52-262 3,365,851 1/1968 Cushman 52-580 3,462,897 8/ 1969 Weinrof 52-90 X FOREIGN PATENTS 134,923 10/ 1949 Australia 52--90 1,540,479 8/1968 France 52--73 ALFRED C. PERHAM, Primary Examiner U.S. Cl. X.R. 

